bad reaction to vaccination

My puppy had a bad reaction to her first shot,
Shaking, couldn't stand( weak) eyes swollen, shaky. Fever
So I brought her to emergency vet last night. Checked for parvo, doesn't have that. The vet said it was just a bad reaction.
Recommended gaterode, rice etc. which I did. 
I watched a close eye on her through the night. Next morning came around, she was all hyper back to her normal self. 
But now I'm wondering she needs her next shot In three weeks, what must I do? What if it happens again? 
New puppy owner:)